Compilare: main.cpp: In function 'void permuteRec(std::vector<int>, int, int, std::vector<int>)': main.cpp:10:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<curr.size();i++)out<<curr[i]<<(i<curr.size()-1 ? " ":"\n"); ~^~~~~~~~~~~~ main.cpp:10:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<curr.size();i++)out<<curr[i]<<(i<curr.size()-1 ? " ":"\n"); ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:20:11: warning: unused variable 'k' [-Wunused-variable] int n,k; ^